1. Field of the Invention
The present invention relates to the stabilization of vehicles. More particularly it relates to a device for attachment to the suspension system of motor vehicles which stabilizes the ride of such vehicles against roll-over, while moving upon a road while concurrently providing relief from the designed stiffness in some suspensions.
2. Prior Art
Modem motor vehicles have evolved to include a suspension system whereby the passenger section of the vehicle is elevated above the axles and wheels of the vehicle. Conventional suspension systems commonly use springs, rubber bushings, and motion stabilizers such as hydraulic shock absorbers, to dampen the effects of bumps and dips in the road surface being traveled, being transmitted to the passengers. The final effect of such suspension systems yielding a more tolerable if not more pleasant ride for the occupants of a vehicle traveling down less than perfectly surfaced roads, which are frequently encountered by vehicle traffic.
Such an arrangement of separating the passenger compartment from the axle and frame of the moving vehicle provides both benefits and drawbacks to the operation of the vehicle. In cases of modem and ever more popular four wheel drive, off road, and suburban utility vehicles (SUV's), the height of the passenger cabin is raised above the axle and frame of the vehicle to provide ground clearance for traversing dirt roads. This elevation of the passenger compartment by the suspension comes at the expense of overall vehicle stabilization which is decreased by raising the center of gravity of such vehicles. Such an increase in the height of the center of gravity yields an undesirable propensity of the vehicle to roll over during turns or other maneuvers. However raising the passenger compartment also yields the benefits of a generally more pleasant ride for occupants of the passengers' compartment from the dampening of shocks transmitted from the road surface, an elevated view of the road, and better ground clearance.
As is obvious, the more such vehicles are raised to achieve ground clearance and road view, the higher the chance of a roll over of the vehicle on a curve or large bump. The effects of a raised center of gravity are exacerbated with any addition of passengers and/or cargo. When such weight-maximized suspensions are loaded with less than their designed carrying ability, the suspension can be too stiff and thereby impart too much road shock to the occupants carried therein.
As such, a need is ever present for an easily installed auxiliary device that would help minimize the chance of roll over of top heavy vehicles, provide better cornering stability, while providing the additional benefit of softening the ride of vehicles with stiff suspensions. Such a device should allow for easy installation to the vehicle it is used upon and should be adjustable to allow for use on varying suspension configurations.
U.S. Pat. No. 2,058,281 (Wesley) addresses the dampening or anti-rebound effect of a top mounted spring, however Wesley is not easily installed, provides no ability for adjustment of the device on the vehicle and is incapable of use on vehicles which have the spring positioned above the axil upon which they ride.
U.S. Pat. No. 5,035,406 (Sellers) teaches an auxiliary leaf spring for attachment to factory leaf springs, to improve the cargo carrying capability of the vehicle. Sellers however, offers no ability to soften the ride afforded by stiff springs when unloaded and is not easily adjustable once installed.
U.S. Pat. No. 4,175,772 and 4,362,318 (Lampert) teach a spring mountable to the vehicle frame and leaf springs at opposing ends which soften lightly loaded stiff suspensions. Lampert however does not offer any roll-over resistance characteristics and requires substantial frame modification of the vehicle with the addition of an auxiliary spring mounting device.
U.S. Pat. No. 3,312,459 (Pence) and U.S. Pat. No. 3,173,668 (Giovinazzzo) both teach vehicle overload springs attachable to the leaf springs of a vehicle. Neither device affords any rollover recovery capability to vehicles and might actually increase rollover tendencies of the vehicle due to the force they provide which pushes the chassis away from the leaf springs supporting it.
U.S. Pat. No. 5,137,300 (Walton) and U.S. Pat. No. 5,024,463 (Oliver) feature variable rate helper springs attachable at one end to the vehicle axle and at the other to the vehicle frame. Both of these patents however fail to offer any roll-over resistance to the vehicle.
As such, there exists a need for an easily and inexpensively manufactured apparatus, which can be readily attached to most conventional leaf springs provided for suspension of vehicles. Such a device should also provide resistance to roll-over, improved dampening of a stiff ride at light loads, and should be adjustable to provide adaptability to various vehicle models and designs.